One man was seriously injured and traffic was snarled for hours when his Chevrolet Malibu collided head-on with a tanker truck on West Boylston Street on Friday afternoon.

The man, whose identity was not released by police, was taken by ambulance to a hospital after the 1:45 p.m. accident. His condition was not available Friday night. No other injuries were reported in the crash, which left five vehicles damaged and delayed traffic on West Boylston Street for almost four hours.

West Boylston Street was closed from Quinsigamond Community College to the Greendale Mall through the evening rush hour and was reopened just before 6 p.m., according to police.

Preliminary work by police determined that the Malibu was going south on West Boylston when it sideswiped a Honda SUV, went out of control and crossed the median, where it collided head-on with a tanker truck. The collision also involved a parked Chrysler PT Cruiser and a parked Kia SUV on the northbound side.

The driver of the Malibu was unconscious when he was taken from the scene, according to District Fire Chief Michael Conley.

Jeff Ladou, owner of Hairsmyth Barber Shop at 326 West Boylston St., said he saw the accident through his shop window and rushed out to help.

The driver was pinned in the driver's seat, he said. It took firefighters about 20 minutes to get him out.

Using a hydraulic tool, they cut the roof off the car to free the victim, according to District Chief Conley.

The crash occurred in front of 322 West Boylston St., which is near Bourne Street.

Jaime Bazydlo, who was getting a tattoo in a nearby shop when he heard the crash, ran out of the shop and saw the wreckage. He said the driver of the car was initially able to talk but that his condition appeared to worsen.

The tanker truck was from C. White Petro-Chemical Transport. While the truck's load did not leak, the diesel fuel the truck was running on was leaking onto the street. Firefighters made dams out of sand at several spots on the street to contain the spill.

The Police Department's Accident Reconstruction Team, Truck Team and Crime Scene Unit responded to the accident.